JP2009161229A - Gas barrier packaging material with masked information - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas barrier packaging material which can indicate various pieces of masked information which cannot be seen without opening a bag and cannot be seen easily from the outside of the bag by using a gas barrier film with a simple layer structure at a low cost. <P>SOLUTION: The gas barrier packaging material with masked information is characterized in that at least an inorganic deposition layer, a pattern printed layer, a masking layer, an information indication layer and a heat seal layer are laminated on the surface of a transparent base film in this order. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a gas barrier packaging material, and more particularly to a packaging material having unique information such as concealed characters and patterns that cannot be seen unless the packaging container or packaging bag is opened.

2. Description of the Related Art Conventionally, a packaging container and a packaging bag having a mechanism in which some information can be viewed only after purchasing a product in a packaging container or a packaging bag and opening the product are known.
The packaging container disclosed by patent document 1 is a packaging container which printed the unique number etc., The place characterized by the laminated material which laminated | stacked at least the outermost film layer, the transparent barrier layer, and the heat seal layer one by one. The outermost film layer is provided with a concealing layer composed of an ink layer, a white ink layer, and a concealing information layer printed by an ink jet recording method, and the heat sealing layer is stacked and sealed so as to face each other. It is a packaging container with a concealing layer. According to this invention, since a barrier film in which an inorganic vapor deposition film made of aluminum oxide or silicon oxide is formed on a base film is used as a transparent barrier layer, a total of three layers of films are laminated. Therefore, there is a problem that the whole thickness becomes thick. In addition, depending on the form of the packaging container and the printed pattern on the surface, there is a problem that information recorded by inkjet may be visible from a transparent window portion having no pattern on the opposite side or side of the container.
JP 2004-67219 A

  The present invention has been made in view of the above-described problems, and the object of the present invention is to use a gas barrier film having a simple layer structure and to display various concealment information that cannot be seen unless opened. It is to provide a gas barrier packaging material that can be displayed so as not to be easily viewed from the outside at a low cost.

  As means for solving the above-mentioned problems, the invention according to claim 1 is characterized in that an inorganic vapor deposition layer, a pattern printing layer, a shielding layer, an information display layer, and a heat seal layer are arranged in this order on the surface of the transparent substrate film. It is a gas barrier packaging material having concealment information characterized by being laminated.

  The invention according to claim 2 is the gas barrier packaging material having concealment information according to claim 1, wherein the surface of the heat seal layer is roughened.

  The invention according to claim 3 is characterized in that the 10-point average roughness Rz of the surface of the heat-sealed heat-sealed layer is 0.5 to 10.0 μm. It is a gas barrier packaging material having.

  The invention according to claim 4 is the gas barrier packaging material having concealment information according to any one of claims 1 to 3, wherein the information display layer is provided by printing. is there.

  The invention according to claim 5 is a gas barrier property having concealment information according to claim 4, wherein the information display layer is printed on an ink layer that changes color by laser light by a laser marking method. It is a packaging material.

  In the invention described in claim 6, a base layer is provided between the shielding layer and the information display layer, and the color of the information display layer and the base layer is black and white, red and white, or brown and yellow. The gas barrier packaging material having concealment information according to claim 5, wherein the packaging material is concealed.

  By using the above means, the packaging material of the present invention has the following effects. The packaging material of the present invention is obtained by laminating an inorganic vapor deposition layer, a pattern printing layer, a shielding layer, an information display layer, and a heat seal layer in this order on the surface of a transparent substrate film. Since the shielding layer is provided under the information display layer, the contents of the information display layer cannot be viewed from the outside of the packaging container. Moreover, since there are only two film layers, a transparent base film and a heat seal layer, the entire thickness can be reduced. When the heat seal layer is provided by extruding molten resin using an extruder, the overall thickness can be further reduced. This is one of the great effects of the present invention.

  In addition, since the shielding layer and the information display layer are provided continuously to the pattern printing layer, depending on the content of the information display layer, the shielding layer and the information display layer can be provided in the same process as the pattern printing. The process can be greatly shortened.

  In addition, when the surface of the heat seal layer is roughened, it is difficult to see the contents of the information display layer through a transparent window without a printed pattern on the opposite side or side of the packaging container. There is an effect that restrictions on the printed pattern are reduced. This effect is effectively exhibited when the surface roughness of the heat seal layer is 0.5 to 10.0 μm in the value of 10-point average roughness Rz.

  Further, when the information content of the information display layer is provided by printing instead of printing, a packaging material having different information (unique information) for each packaging container can be easily obtained. The term “printing” used here is a term used in contrast to normal printing in which the same contents are repeatedly formed, and is used in the meaning of variable information printing that can easily change the contents.

  Furthermore, when the information display layer is printed on the ink layer that changes color by laser light by the laser marking method, laser marking can be performed by penetrating the heat seal layer after the heat seal layer is provided. Therefore, for example, marking can be performed immediately before being formed into a packaging container in a bag making machine, which makes it easy and safe to manage unique information, and at the time of product planning using unique information. Accurate operation along the line is possible.

  Furthermore, when a base layer is provided between the shielding layer and the information display layer, and the color of the information display layer and the base layer is a combination of black and white, red and white, brown and yellow, the displayed information Not only the visibility is improved, but also information display excellent in design becomes possible.

Embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic cross-sectional view showing a basic embodiment of a packaging material according to the present invention. As the transparent base film 1, the following synthetic resin film including a general synthetic resin film usually used as a flexible packaging material can be used. Specifically, polyolefin resins such as low density polyethylene (LDPE), high density polyethylene (HDPE), linear low density polyethylene (LLDPE), polypropylene (PP), polyolefin elastomer, polyethylene terephthalate (PET), polyethylene Polyester resins such as naphthalate (PEN), cellulose resins such as cellophane and cellulose triacetate (TAC), ethylene-vinyl acetate copolymer resins (EVA), ionomer resins, polybutene resins, polyacrylonitrile resins, polyamides Synthetic resin films such as polyurethane resin, polystyrene resin (PS), polyvinyl chloride resin (PVC), polyvinylidene chloride resin (PVDC), polycarbonate resin (PC), fluorine resin, urethane resin, etc. For It can be used depending on.

  Next, the inorganic vapor deposition layer 2 is provided on the surface of the transparent substrate film 1. The inorganic vapor-deposited layer 2 is formed for the purpose of enhancing gas barrier properties such as oxygen and water vapor, and includes, as its material, simple metals such as chromium, tin, and aluminum, magnesium oxide, aluminum oxide, zinc oxide, tin oxide, titanium oxide, Metal oxides such as silicon oxide, and mixtures thereof can be used. Among these, a vapor deposition layer of aluminum oxide or silicon oxide is most suitable from the viewpoints of transparency, hygiene and gas barrier properties.

  As a method for forming the inorganic vapor deposition layer 2, a known means such as a physical vapor deposition method such as a vacuum vapor deposition method, a sputtering method or an ion plating method, or a chemical vapor deposition method such as a plasma chemical vapor deposition method is used. As thickness of the inorganic vapor deposition layer 2, 5-50 nm is common.

  In order to protect and reinforce the inorganic vapor deposition layer 2, a barrier coat layer 2a may be provided as shown in FIG. As the barrier coat layer, a two-component acrylic urethane resin that is coated with a resin having a relatively high gas barrier property such as an ethylene-vinyl acetate copolymer resin, a vinylidene chloride resin, a polyvinyl alcohol resin, or is usually used as a protective layer for a printing layer. Alternatively, an organic-inorganic hybrid resin solution in which a metal alkoxide such as tetraethoxysilane is dissolved and dispersed in a water-soluble resin such as polyvinyl alcohol resin can be preferably used.

Next, the pattern printing layer 3 will be described. The pattern printing layer 3 can form an arbitrary pattern, character, or the like according to the intended packaging container. Usually, a gravure rotary multicolor printing machine is used, and a necessary pattern, character, etc. are printed using the gravure ink for soft packaging normally used for packaging materials. At this time, the shielding layer 4, the information display layer 5, and the base layer 5a may be provided simultaneously.
The shielding layer 4 is provided to conceal the information on the information display layer 5 from the outside of the packaging container through the transparent base film 1 and is black or white depending on the relationship with the overall pattern. The ink is formed using an ink having a high concealment property of other color tone. The shape of the shielding layer 4 is generally larger than that of the intended information display layer from the viewpoint of ease of printing. However, depending on the type of the pattern, In some cases, it is a solid print.

  Next, the information display layer 5 is formed on the shielding layer 4. The formation method of the information display layer 5 varies depending on the type of information to be displayed. For example, if there is a hit and miss at a certain ratio, such as a lottery, and this ratio is high in frequency such as 1: 4, the imposition of the same pattern It can be formed by printing with imposition so that the ratio of hit and miss is 1: 4. In this case, since it can be formed by using one color of a gravure printing machine, the information display layer 5 can be formed very easily and therefore at a low cost.

If the information to be displayed is something that cannot be expressed simply by repeating printing, it can be formed by printing. As described above, the printing here is a term used in contrast to normal printing, and is sometimes called variable information printing. As a device for performing such printing, there are a number printing device, a stamp device, an ink jet device, a laser marking device, and the like.
By performing printing separately from gravure printing using these devices, for example, it is possible to print hit and miss at an arbitrary ratio, or to print unique information with no two identical numbers. . The information display layer 5 is formed by these methods. This process may be performed simultaneously with the printing process by using a printing apparatus incorporated in a printing machine, and a printing process is provided separately from the printing process. You may carry out.
The contents of the information expressed by this printing are not necessarily limited to numbers and symbols, and may be expressed as sentences, such as fortune cards, or as barcodes.

  Among the embodiments of the present invention, as a particularly effective form, a laser is passed through the heat seal layer immediately before the heat seal layer 6 is provided and processed as a packaging container by a bag making machine after slitting. An embodiment in which information is written by a marking device is possible. According to this method, since the information display layer 5 is already protected by the heat seal layer 6, the information display layer 5 is rubbed in the bag-making process after writing information or rubbed with the contents after becoming a product. In addition to preventing the occurrence of wear, dirt, etc., in order to write information at a location very close to the final process, for example, information management at the final product stage is performed regardless of the occurrence of defective products during the intermediate process. Therefore, accurate product management is realized.

As a means for displaying information by such a laser marking method, it is preferable that the information display layer 5 be an ink layer that is discolored by laser light.
As such an ink layer, depending on the type of laser light source used, for example, a carbon dioxide laser is 10640 nm, a YAG laser is 1064 nm, an Nd: YVO4 laser is an ink added with a material having absorption at 1064 nm. Can be used.

  Further, a base layer 5a is provided between the information display layer 5 and the shielding layer 4, and the color tone of the information display layer 5 and the base layer 5a has a contrast such as black and white, red and white, brown and yellow. By combining the color tones, the visibility and design of the information display layer are improved, and the concealability from the outside of the packaging container is also improved. For example, the information display layer may be black and the base layer may be white, or the information display layer may be white and the base layer may be black. About the combination of these colors, it selects suitably by the design of the target packaging container. The combination of the colors of the information display layer and the base layer is not limited to the above combination, but a particularly preferable result is obtained in the case of the above combination.

Next, the heat seal layer 6 is formed on the printing surface of the obtained printed sheet.
The heat seal layer 6 is provided for thermocompression bonding of the inner surfaces in the process of forming the packaging material into the packaging container by the bag making machine, and is intended to protect the printed surface and directly touch the contents. It also plays a variety of roles arising from certain things.
As a material of the heat seal layer 6, a known thermoplastic resin is selected according to the type of the target packaging container. Commonly used materials include low density polyethylene (LDPE), high density polyethylene (HDPE), linear low density polyethylene (LLDPE), polypropylene (PP), and ethylene-vinyl acetate copolymer resin (EVA). , Polyamide resin, polyvinyl chloride resin (PVC), and the like.

  As a method of forming the heat seal layer 6, there are a method in which a resin previously molded into a film shape is bonded with an adhesive, and a method in which a molten resin is extruded into a film shape with an extruder and bonded. The latter method is preferable for the purpose of the present invention because it is easy to form a thin heat seal layer, but is not particularly limited.

When the surface of the heat seal layer 6 is roughened, the portion of the window without the printed pattern on the packaging container becomes translucent, so that the contents of the information display layer can be seen through the opposite side or side of the packaging container. This makes it difficult to obtain favorable results for the purpose of the present invention.
The degree of the rough surface of the heat-sealed heat-seal layer surface 7 is more preferably 0.5 to 10.0 μm in the 10-point average roughness Rz, and the surface roughness of the heat-seal layer is within this range. Although the contents can be visually recognized from the window portion having no printed pattern, it is difficult to see the information on the information display layer through the side view. If this value is smaller than 0.5 μm, the information in the information display layer may be seen through from the side. If it is larger than 10.0 μm, not only will there be a problem in the visibility of the contents from the transparent window, but the information on the information display layer may be difficult to see.
The degree of roughness should be selected according to the intended use and design of the packaging container, but the most preferable range is generally 2.5 to 7.0 μm.
As a method of forming a rough surface on the surface of the heat seal layer, a rough surface is formed on the surface of a cooling roll where the melted resin comes into contact and solidifies when the film having the rough surface processed is bonded or bonded by an extruder. It can be done by processing.
Next, the present invention will be described more specifically based on examples.

As shown in FIG. 1, a PET film having a thickness of 12 μm was used as the transparent substrate film 1, and an inorganic vapor deposition layer 2 made of aluminum oxide was formed on this one side by a physical vapor deposition method to a thickness of 15 nm. Next, using an eight-color gravure rotary printing machine, a pattern printing layer 3 consisting of a total of six colors of yellow, magenta, cyan, black, one special color, and white, a shielding layer 4 with black ink, and an information display layer with white ink 5 was provided by gravure printing. The content of the information display layer 5 is printed at a ratio of 1: 5 for hit and miss. An LLDPE heat seal layer 6 was formed to a thickness of 60 μm on the obtained printed matter using an extruder. The obtained packaging material has a necessary gas barrier property while being thin and thin with a total thickness of less than 80 μm. After slitting this, it was formed into a packaging container by a bag making machine. The contents were then sealed and heat sealed to obtain the intended packaged product. The information on the information display layer provided in a part of the packaging container was not visible from the outside of the packaged product, and it was not possible to recognize the hit unless it was opened. The gas barrier property of the packaging material was measured and found to be 1.00 CC / m ² · day · atm.

As shown in FIG. 2, a PET film having a thickness of 12 μm was used as the transparent substrate film 1, and an inorganic vapor deposition layer 2 made of aluminum oxide was formed to a thickness of 15 nm on one side using a physical vapor deposition method. Next, the barrier coat layer 2a was provided using a coater. As the barrier coat layer, a coating solution in which silica was dispersed in a two-component acrylic urethane resin for the purpose of preventing blocking was used. Next, using an eight-color gravure rotary printing machine, a pattern printing layer 3 consisting of a total of six colors of yellow, magenta, cyan, black, one special color, and white, and a black shielding layer 4, using colorless laser marker ink The information display layer 5 was provided, and then the heat seal layer 6 of LLDPE was formed to a thickness of 60 μm using an extruder. In forming the heat seal layer 6, the surface of the cooling roll in contact with the LLDPE was roughened so that the surface 7 of the heat seal layer 6 was rough. When the roughness of the heat seal layer surface 7 was measured with a surface roughness meter, the 10-point average roughness Rz was 5.0 μm.
The obtained packaging material is slitted, and the laser marking device is used to create unique information consisting of 7-digit alphanumeric characters on the information display layer 5 through the heat seal layer 6 immediately before creating the packaging container by using a bag making machine. Printed on. The colorless laser marker ink changed its color to black only in the portion printed by the laser marking device. The contents were then sealed and heat sealed to obtain the intended packaged product.
The information on the information display layer 5 provided in a part of the packaging container was not visible from the outside of the packaged product, and the information content was not visible even when viewed through the back side of the container or the transparent window. .

As shown in FIG. 3, a PET film having a thickness of 12 μm was used as the transparent substrate film 1, and an inorganic vapor-deposited layer 2 made of aluminum oxide was formed on this one side by a physical vapor deposition method to a thickness of 15 nm. Next, the barrier coat layer 2a was provided using a coater. As the barrier coat layer, a coating solution in which tetraethoxysilane was dissolved and dispersed in a polyvinyl alcohol resin was used. Next, using a 10-color gravure rotary printing machine, a pattern printing layer 3 composed of a total of 7 colors of yellow, magenta, cyan, black, 2 special colors, and white, a sepia shielding layer 4, a yellow base layer 5a, Further, an information display layer 5 using colorless laser marker ink was provided, and then an LLDPE heat seal layer 6 was formed to a thickness of 60 μm using an extruder. In forming the heat seal layer 6, the surface of the cooling roll in contact with the LLDPE was roughened so that the surface 7 of the heat seal layer 6 was rough. When the roughness of the heat seal layer surface 7 was measured with a surface roughness meter, the 10-point average roughness Rz was 5.0 μm.
Using the laser marking device, the unique information consisting of 7-digit alphanumeric characters is put on the information display layer 5 through the heat-seal layer at the stage just before slitting the obtained packaging material and creating the packaging container with a bag making machine. Printed. The ink for the laser marker on the printed part turned brown. The contents were then sealed and heat sealed to obtain the intended packaged product.
The information on the information display layer provided in a part of the packaging container was not visible from the outside of the packaged product, and the information content was not visible even when viewed through the back side of the container or the transparent window.

Schematic cross-sectional view showing a basic embodiment of the packaging material according to the present invention. Sectional schematic diagram showing an example of an embodiment of the packaging material according to the present invention Sectional schematic diagram showing an example of an embodiment of the packaging material according to the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Transparent base film 2 ... Inorganic vapor deposition layer 2a ... Barrier coat layer 3 ... Pattern printing layer 4 ... Shielding layer 5 ... Information display layer 5a ... Base layer 6 ... Heat seal layer 7 ... Surface of the heat seal layer that has been roughened

Claims (6)

  A gas barrier packaging material having concealment information, characterized in that at least an inorganic vapor deposition layer, a pattern printing layer, a shielding layer, an information display layer, and a heat seal layer are laminated in this order on the surface of a transparent substrate film.   The gas barrier packaging material having concealment information according to claim 1, wherein a surface of the heat seal layer is roughened.   The gas barrier packaging material having concealment information according to claim 2, wherein the 10-point average roughness Rz of the surface of the heat-sealed heat-sealed layer is 0.5 to 10.0 µm.   The gas barrier packaging material having concealment information according to any one of claims 1 to 3, wherein the information display layer is provided by printing.   5. The gas barrier packaging material having concealment information according to claim 4, wherein the information display layer is printed on an ink layer that changes color by laser light by a laser marking method.   The underlayer is provided between the shielding layer and the information display layer, and the color of the information display layer and the underlayer is a combination of black and white, red and white, or brown and yellow. A gas barrier packaging material having the concealment information according to 5.